Better understanding leads to better results.
Visuals have been found to improve learning by up to 400 percent. Also, they affect learners on a cognitive level and stimulate imagination, therefore, enabling users to process the information faster.
"When words and visual elements are closely entwined, we create something new and we augment our communal intelligence ... visual language has the potential for increasing ‘human bandwidth'—the capacity to take in, comprehend, and more efficiently synthesize large amounts of new information."
-Robert E. Horn, Stanford University
Visuals cause a faster and stronger reaction than words. They help users engage with the content, and such emotional reactions influence information retention. This is because the visual memory is encoded in the medial temporal lobe of the brain, the same place where emotions are processed. The brain is set up in a way that visual stimuli and emotional response is easily linked, and together the two form memories.